import React, { Component } from 'react'
import {nanoid} from 'nanoid'
import PropTypes from 'prop-types'

import './index.css'
export default class Header extends Component {
  static propTypes = {
    addTodo:PropTypes.func.isRequired
  }

  handleKeyUp = (event) => {
    const { keyCode,target } = event
    if(keyCode !== 13) return
    if(target.value.trim() ===''){
      alert('输入不能为空')
      return
    }
    const todoObj = {id:nanoid(),name:target.value,done:false}

    this.props.addTodo(todoObj)
    target.value = ''
  }
  render() {
    return (
      <div>  <div className="todo-header">
      <input onKeyUp = {this.handleKeyUp} type="text" placeholder="请输入你的任务名称，按回车键确认"/>
    </div></div>
    )
  }
}
